Radiation curable coatings for use on a variety of substrates and curable by exposure to ionizing irradiation or ultraviolet light are well known. The use of urethane type coatings cured with ultraviolet light to provide protective wear layers for wall or floor tile is for instance described in U.S. Pat. No. 4,180,615. U.S. Pat. No. 3,918,393 describes a method for obtaining a non-glossy coating on various substrates by curing radiation sensitive material with ionizing irradiation or ultraviolet light in two stages. In this process the coating is partially cured in an oxygen-containing atmosphere and the curing is completed in an inert atmosphere. U.S. Pat. No. 4,122,225 discloses method and apparatus for coating tile which involves the application on one coat of radiation curable material to an entire substrate followed by partial curing and the subsequent application and curing of a second coat of radiation curable material only on high areas of the substrate which are subject to greater than average wear.